Vehicle seat

ABSTRACT

To improve workability when attaching an airbag module disposed in a side portion of a vehicle seat from a seat back side. A vehicle seat (S) includes: a side frame ( 13 ) which constitutes a side portion of a seat back frame ( 10 ); a bracket ( 20 ) which includes an attachment portion ( 21 ) attached to a side surface of the side frame ( 13 ) on a seat inner side and a back protrusion portion ( 22 ) protruding backward from the attachment portion ( 21 ); and an airbag module ( 30 ) which includes a retainer ( 34 ) fixed to the back protrusion portion ( 22 ).

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is entering into the national phase of PCT ApplicationNumber PCT/JP2017/035150, filed on Sep. 28, 2017, which claims thebenefit of priority from the Japanese Patent Application Number2016-216090, filed on Nov. 4, 2016, Japanese Patent Application Number2017-014369, filed on Jan. 30, 2017, and Japanese Patent ApplicationNumber 2017-029330, filed on Feb. 20, 2017, the entire contents of whichare incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a vehicle seat having an airbagprovided in a side portion.

BACKGROUND ART

A vehicle seat equipped with a side airbag device which expands anddeploys an airbag provided in a side portion of a vehicle seat in theevent of side collision and protects an occupant is known (for example,see Patent Literature 1 below).

CITATION LIST Patent Literature

PATENT LITERATURE 1: JP 5669567 B2

SUMMARY OF INVENTION Technical Problem

In the above-described related art, an airbag module is attached to abracket which extends from a side frame toward a seat front side. Forthat reason, the workability when attaching the airbag module from aseat back side to the seat frame was low.

The present invention has been made in view of the above-describedproblem and an object of the present invention is to provide a vehicleseat which improves workability when attaching an airbag module disposedin a side portion of a vehicle seat from a seat back side.

Solution to Problem

According to the vehicle seat of the present invention, theabove-described problems are solved by including: a side frame whichconstitutes a side portion of a seat back frame; a bracket whichincludes an attachment portion attached to a side surface of a sideframe on a seat inner side and a back protrusion portion protrudingbackward from the attachment portion; and an airbag module which isfixed to the back protrusion portion.

According to the above-described vehicle seat, since the bracket forattaching the airbag module is attached to the inner surface of the sideframe, it is possible to obtain a compact width of the attachmentportion of the airbag module in the right and left direction. Further,since the airbag module is attached to a back side in relation to theattachment portion between the bracket and the side frame, it ispossible to improve workability when assembling the airbag module fromthe seat back side to the bracket.

Further, in the above-described vehicle seat, the side frame may includea cylindrical pipe frame and a plate-shaped plate frame attached to alower portion of the pipe frame, and the airbag module may be attachedto a side surface of the plate frame on a seat outer side.

In this way, it is possible to attach the airbag module to both of thebracket and the side surface of the plate frame on the seat outer side.Accordingly, it is possible to strongly attach the airbag module to aseat cushion frame as compared with a case in which the airbag module isattached to any one of the bracket and the plate frame.

Further, in the above-described vehicle seat, the bracket may beattached to a lower portion in relation to a joint portion between thepipe frame and the plate frame in the pipe frame.

In this way, since the bracket is attached a portion below the jointportion between the pipe frame and the plate frame in the side frame,that is, a portion not overlapping the joint portion, it is possible toprevent improvement of rigidity of the side frame. Accordingly, it ispossible to maintain appropriate shock absorption of the side frame evenwhen the bracket is attached.

Further, in the above-described vehicle seat, the back protrusionportion may include a back extension portion which extends backward fromthe attachment portion and an outer extension portion which extends fromthe back extension portion toward a seat outer side, and the airbagmodule may be attached to the outer extension portion.

In this way, it is possible to set the direction of the attachmentportion to the pipe frame and the direction of the attachment portion tothe airbag module in the bracket to be different from each other.Accordingly, it is possible to improve attachment workability bypreventing interference between attachment positions of the bracket andthe pipe frame and between attachment positions of the bracket and theairbag module.

Further, in the above-described vehicle seat, the airbag module mayinclude an airbag, an inflator which supplies a gas to the airbag, acasing which covers the inflator and the airbag, and a retainerincluding a protrusion portion which protrudes from the casing, and theouter extension portion of the bracket and the protrusion portion of theretainer may be fixed.

In this way, it is possible to fix the retainer protruding from theairbag module and the bracket. Accordingly, it is possible to improveworkability when attaching the airbag module to the bracket.

Further, in the above-described vehicle seat, the outer extensionportion of the bracket and the protrusion portion of the retainer may befixed by fastening a nut to a bolt penetrating both portions, and theprotrusion portion of the retainer may be provided with an openingportion through which the bolt is inserted.

In this way, it is possible to easily fix the retainer of the airbagmodule and the bracket by using the bolt and the nut. Accordingly, it ispossible to easily perform an operation of attaching the airbag moduleto the bracket.

Further, in the above-described vehicle seat, the protrusion portion ofthe retainer may include an inner extension portion which is provided ona back side of the side frame to extend toward the inner side of theseat, and the inner extension portion and the outer extension portionmay be fixed.

In this way, it is possible to easily fix the retainer of the airbagmodule and the bracket from the seat back side by using the bolt and thenut. Accordingly, it is possible to easily perform an operation ofattaching the airbag module to the bracket.

Further, in the above-described vehicle seat, an end portion of the boltmay face backward and the nut may be a cap nut which covers the endportion of the bolt.

In this way, it is possible to easily perform an operation of fasteningthe nut to the bolt from the seat back side.

Further, since the end portion of the bolt is covered by the cap nut, itis possible to prevent the seat inner portion from being damaged by theend portion of the bolt.

Further, in the above-described vehicle seat, the opening portion of theretainer may be provided across an end portion on the inner side of theseat.

In this way, it is possible to fit the opening portion provided in theretainer to the bolt from the seat outer side. Accordingly, it ispossible to easily perform an operation of attaching the airbag moduleto the bracket.

Further, the above-described vehicle seat may include a seat back padwhich covers the seat back frame and the seat back pad may include astorage portion which is opened in the side portion toward a seat outerside and stores the airbag module.

In this way, it is possible to attach the airbag module by disposing theair bag module in the storage portion of the seat back pad even afterthe seat back pad is attached to the seat back frame. In this way, sinceit is possible to attach the airbag module after the seat back pad isattached to the seat back frame, no displacement of the airbag moduleoccurs when attaching the seat back pad. Accordingly, it is possible toimprove the arrangement accuracy of the airbag module.

Advantageous Effects of Invention

According to the present invention, it is possible to improve theworkability when attaching the airbag module disposed in the sideportion of the vehicle seat from the seat back side.

According to an aspect of the present invention, it is possible tostrongly attach the airbag module to the seat cushion frame.

According to an aspect of the present invention, it is possible tomaintain appropriate shock absorption of the side frame even when thebracket is attached.

According to an aspect of the present invention, it is possible toimprove attachment workability by preventing an interference betweenattachment positions of the bracket and the pipe frame and betweenattachment positions of the bracket and the airbag module.

According to an aspect of the present invention, it is possible toimprove workability when attaching the airbag module to the bracket.

According to an aspect of the present invention, it is possible toeasily fix the retainer of the airbag module and the bracket by using abolt and a nut.

According to an aspect of the present invention, it is possible toeasily fix the retainer of the airbag module and the bracket from theseat back side by using a bolt and a nut.

According to an aspect of the present invention, it is possible toprevent the seat inner portion from being damaged by the end portion ofthe bolt.

According to an aspect of the present invention, it is possible to fitthe opening portion provided in the retainer to the bolt from the seatouter side.

According to an aspect of the present invention, it is possible toattach the airbag module by disposing the airbag module in the storageportion of the seat back pad even after the seat back pad is attached tothe seat back frame.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of a vehicle seat according to the presentembodiment.

FIG. 2 is a perspective view of a seat back frame.

FIG. 3 is a right view of the seat back frame.

FIG. 4 is a left view of the seat back frame.

FIG. 5 is an enlarged view of a position in which an airbag module isattached to a pipe frame.

FIG. 6 is a cross-sectional view taken along a line VI-VI of FIG. 5.

FIG. 7 is a cross-sectional view taken along a line VII-VII of FIG. 5.

FIG. 8 is an enlarged view of a portion in which an airbag module isattached to a plate frame.

FIG. 9 is a cross-sectional view taken along a line IX-IX of FIG. 1.

FIG. 10 is a perspective view illustrating a modified example in whichthe arrangement of an inflator in a seat back frame is changed.

FIG. 11 is a right view of a seat back frame.

FIG. 12 is a perspective view of a retainer.

FIG. 13 is a perspective view of the seat back frame.

FIG. 14 is an enlarged view of a position in which an airbag module isattached to a pipe frame.

FIG. 15 is a cross-sectional view taken along a line XV-XV of FIG. 14.

FIG. 16 is a cross-sectional view taken along a line XVI-XVI of FIG. 14.

FIG. 17 is a perspective view of the retainer.

FIG. 18 is an enlarged view of a position in which an airbag module isattached to a pipe frame in a vehicle seat according to a modifiedexample of the present invention.

DESCRIPTION OF EMBODIMENTS

<<1>>

Hereinafter, a vehicle seat S according to an embodiment of the presentinvention (hereinafter, the embodiment) will be described with referenceto FIGS. 1 to 10. The vehicle seat S according to the embodiment is avehicle seat which includes an airbag device provided in a side portion.

Additionally, the embodiment to be described below is merely an examplefor easily understanding the present invention and does not limit thepresent invention. That is, the shapes, dimensions, arrangements, andthe like of the members to be described below can be modified andimproved without departing from the spirit of the present invention andthe equivalents thereof are, of course, also included in the presentinvention.

In the description below, the “front to back direction” means the frontto back direction when viewed from the seated person of the vehicle seatS and corresponds to a direction matching a vehicle traveling direction.

The “seat width direction” means a horizontal width direction of thevehicle seat S and matches the right and left direction when viewed fromthe seated person of the vehicle seat S.

Further, the “up to down direction” means the height direction of thevehicle seat S and matches the up to down direction when the vehicleseat S is viewed from the front side.

[Configuration of Vehicle Seat S]

As illustrated in FIG. 1, the vehicle seat S includes a seat back S1which becomes a backrest portion, a seat cushion S2 which becomes aseated portion, and a headrest S3 which is disposed at an upper portionof the seat back S1 and supports a head of an occupant.

The seat back S1 has a configuration in which a seat back frame 10corresponding to a skeleton illustrated in FIG. 2 is covered by a seatback pad 1 and the seat back pad 1 is further covered by a skin 2.

An airbag module 30 and an airbag module 40 are respectively providedinside the side portion of the seat back S1.

In the present embodiment, the airbag module 40 is set to be closer to adoor of a vehicle in relation to the airbag module 30. That is, theairbag module 30 is referred to as a far-side airbag device and theairbag module 40 is referred to as a near-side airbag device.

Additionally, the airbag module 30 which is the far-side airbag deviceis used to protect an occupant of the vehicle seat S from the collisionwith an occupant seated on a next seat.

Further, the airbag module 40 which is the near-side airbag device isused to protect the occupant of the vehicle seat S from the collisionwith the door of the vehicle or the outside of the vehicle.

In the present embodiment, an example in which the airbag module 30corresponding to the far-side airbag device is disposed at the rightside of the vehicle seat S and the airbag module 40 corresponding to thenear-side airbag device is disposed at the left side thereof isdescribed, but the arrangement of both modules is determined in responseto the arrangement of the vehicle seat S in the vehicle and is notlimited to the above-described example.

[Configuration of Seat Back S1]

Next, a configuration of the seat back S1 will be described withreference to FIGS. 2 to 9.

FIG. 2 shows a perspective view of the seat back frame 10 which is askeleton of the seat back S1.

As illustrated in FIG. 2, the seat back frame 10 includes an inverseU-shaped pipe frame 11, a pair of plate frames 12 which respectivelyforms end portions in the seat width direction, and a lower frame 15which is bridged between the lower end portions of the pair of plateframes 12.

A side portion 11A of the pipe frame 11 and an upper end portion of theplate frame 12 are respectively disposed to overlap each other in the upto down direction and the side portion 11A of the pipe frame 11 and theupper end portion of the plate frame 12 are joined at a welded portionincluding a welded portion 50A and a welded portion 50B.

Additionally, in the present embodiment, the side portion of the seatback frame 10 which includes the side portion 11A of the pipe frame 11and the plate frame 12 is referred to as a side frame 13.

The seat back frame 10 is provided with a cross member 14 which bridgesthe upper portion of the pipe frame 11 (that is, the upper portion ofthe side portion 11A).

The airbag module 30 is attached to the right side frame 13 through abracket 20. Additionally, since the bracket 20 is provided at a lowerportion in relation to the welded portion 50A and the welded portion 50Bcorresponding to the joint portion between the pipe frame 11 and theplate frame 12, it prevents rigidity of the joint portion from beingincreased more than necessary. Accordingly, the shock absorption of theseat back frame 10 is not disturbed by the attachment of the bracket 20and the airbag module 30.

[Attachment Structure of Airbag Module 30]

Hereinafter, an attachment structure of the airbag module 30 withrespect to the bracket 20 will be described in detail with reference toFIG. 3 and FIGS. 5 to 9.

As illustrated in FIGS. 5 and 6, a side surface of the side portion 11Aof the right pipe frame 11 on the seat inner side is provided with athrough-hole 11B and a through-hole 11C which are formed at the upperand lower sides.

Here, the bracket 20 includes an attachment portion 21 which is attachedto the through-hole 11C of the pipe frame 11 and a back protrusionportion 22 which protrudes from the attachment portion 21 backward.Additionally, the back protrusion portion 22 includes a back extensionportion 22A which extends from the attachment portion 21 toward the seatback side and an outer extension portion 22B which extends from the backextension portion 22A toward the seat outer side.

A screw 23 is fastened to the through-hole formed in the attachmentportion 21 of the bracket 20 and the through-hole 11C formed in thebracket 20 so that the bracket 20 is fixed to the pipe frame 11.

As illustrated in FIGS. 3, 5, and 7, the airbag module 30 includes anairbag 31, an inflator 32, and a retainer 34 provided inside a casing33.

The inflator 32 generates a gas when receiving an input of an operationsignal via a harness 35 from a sensor detecting collision of thevehicle. Then, the inflator 32 expands and deploys the airbag 31 byinjecting a generated gas into the airbag 31.

The retainer 34 is a plate member for attaching the airbag module 30 tothe seat back frame 10. The retainer 34 includes a flat plate portion34D which faces an outer surface 12A of the plate frame 12 and aprotrusion portion 34A which protrudes from the casing 33.

As illustrated in FIG. 8, a stud bolt 36A and a stud bolt 36B which areprovided in the inflator 32 protrude toward the seat inner side throughthe flat plate portion 34D of the retainer 34. Each of the stud bolt 36Aand the stud bolt 36B passes through the through-hole formed in theplate frame 12.

Then, the inflator 32, the retainer 34, and the plate frame 12 are fixedby fastening a nut to the stud bolt 36A from the seat inner side of theplate frame 12.

Meanwhile, the inflator 32 and the retainer 34 are fixed by fastening anut 37 to the stud bolt 36B. Additionally, the through-hole of the plateframe 12 through which the stud bolt 36B passes has a diameter largerthan that of the nut 37 and the retainer 34 and the plate frame 12 arenot fixed at this portion.

Further, a webbing clip 60 for fixing a webbing is attached to the plateframe 12 at a position interposing the stud bolt 36A and the stud bolt36B in the vertical direction. Here, the webbing is a member that guidesthe deploying direction of the airbag 31 by covering the side portion ofthe airbag module 30.

As illustrated in FIG. 5, the outer extension portion 22B of the bracket20 is attached to the protrusion portion 34A of the retainer 34.

Specifically, as illustrated in FIGS. 5 and 7, the protrusion portion34A includes an inner extension portion 34B which extends toward theseat inner side and an opening portion 34C is formed from the center ofthe inner extension portion 34B to the end portion on the seat innerside.

Then, a bolt 24 passes through the through-hole formed in the outerextension portion 22B of the bracket 20 and the opening portion 34C anda cap nut 25 is fitted to an end portion 24A of the bolt 24 to befastened thereto. Accordingly, the bracket 20 and the retainer 34 arefixed.

Additionally, according to the above-described configuration, the endportion 24A of the bolt 24 faces the seat back side and the cap nut 25can be fitted thereto from the seat back side. Further, since the endportion 24A of the bolt 24 is covered by the cap nut 25, it is possibleto prevent the end portion 24A of the bolt 24 from damaging the insideof the seat back S1.

As illustrated in FIG. 9, a side portion on the arrangement side of theairbag module 30 in the seat back pad 1 of the seat back S1 is providedwith a storage portion 1A in which a pad member is hollowed out. Theairbag module 30 is disposed in the storage portion 1A.

In this way, since the storage portion 1A for disposing the airbagmodule 30 therein is provided in the seat back pad 1, it is possible toattach the airbag module 30 to the seat back frame 10 after the seatback pad 1 is assembled to the seat back frame 10 in the seat back S1.For this reason, it is possible to prevent the displacement of theairbag module 30 as compared with a case in which the seat back pad 1 iscovered by the seat back frame 10 after the airbag module 30 is attachedto the seat back frame 10.

Next, an attachment structure of the airbag module 40 with respect tothe seat back frame 10 will be described. Additionally, the airbagmodule 40 faces an outer surface of a side plate 41 attached to the leftside frame 13 of the seat back frame 10 to be attached.

As illustrated in FIG. 9, the side plate 41 is fixed to the pipe frame11 by threading a screw 42 into the through-hole of the pipe frame 11 onthe seat inner side and the through-hole provided in the side plate 41.

Further, as illustrated in FIG. 4, the position of the upper end of theairbag module 30 is higher than the upper end of the side plate 41 towhich the airbag module 40 is attached. That is, the upper end of theairbag module 30 is located at a position higher than the upper end ofthe airbag module 40.

According to the above-described vehicle seat S, since the bracket 20for attaching the airbag module 30 is attached to the inner surface ofthe side frame 13, it is possible to obtain a compact width of theattachment portion of the airbag module 30 in the right and leftdirection. Further, since the airbag module 30 is attached to the seatback side in relation to the attachment portion between the bracket 20and the side frame 13, it is possible to improve workability whenassembling the airbag module 30 to the bracket 20 from the seat backside.

Further, according to the vehicle seat S, it is possible to attach theairbag module 30 to both of the bracket 20 and the outer surface 12A ofthe plate frame 12. Accordingly, it is possible to strongly attach theairbag module 30 as compared with a case in which the airbag module 30is attached to any one of the bracket 20 and the plate frame 12.

Further, according to the vehicle seat S, since the bracket 20 isattached to a position below the joint portion (the welded portion 50Aand the welded portion 50B) between the pipe frame 11 and the plateframe 12 in the side frame 13, that is, a position not overlapping thejoint portion, it is possible to prevent improvement of rigidity of theside frame 13. Accordingly, it is possible to maintain appropriate shockabsorption of the side frame 13 even when the bracket 20 is attached.

Further, according to the vehicle seat S, it is possible to set thedirection of the attachment portion to the pipe frame 11 and thedirection of the attachment portion to the airbag module 30 in thebracket 20 to be different from each other. Accordingly, it is possibleto improve attachment workability by preventing interference betweenattachment positions of the bracket 20 and the pipe frame 11 and betweenattachment positions of the bracket 20 and the airbag module 30.

Further, according to the vehicle seat S, it is easy to attach thebracket 20 and the retainer 34 of the airbag module 30 from the seatback side by using the bolt 24 and the cap nut 25.

Further, since the end portion 24A of the bolt 24 is covered by the capnut 25, it is possible to prevent the seat back pad 1 from being damagedby the end portion 24A of the bolt 24.

Further, according to the vehicle seat S, it is possible to fit theopening portion 34C of the retainer 34 to the bolt 24 from the seatouter side. Accordingly, it is possible to improve attachmentworkability of the airbag module 30.

Further, according to the vehicle seat S, since the storage portion 1Awhich stores the airbag module 30 is provided in the side portion of theseat back pad 1, the airbag module 30 can be disposed and attached inthe storage portion 1A of the seat back pad 1 even after the seat backpad is attached to the seat back frame 10. In this way, since it ispossible to attach the airbag module 30 after the seat back pad 1 isattached to the seat back frame 10, it is possible to prevent thedisplacement of the airbag module 30 when attaching the seat back pad 1.Accordingly, it is possible to improve the arrangement accuracy of theairbag module 30.

OTHER EMBODIMENTS

Further, the present invention is not limited to the above-describedembodiment.

For example, as illustrated in FIG. 10, the inflator 32 may be disposedat the outside of the casing 33 of the airbag module 30. At this time,the inflator 32 is disposed between a front wall portion 15A which islocated in the lower frame 15 on the seat front side to support a waistportion of an occupant and a back wall portion 15B which is located onthe seat back side.

Additionally, the stud bolt 36A and the stud bolt 36B attached to theinflator 32 pass through the through-holes provided in the back wallportion 15B and are fixed to the back wall portion 15B by nuts.

Further, the inflator 32 and the airbag 31 are connected by a pipe 38and a gas generated from the inflator 32 is injected to the airbag 31through the pipe 38.

In this way, since the inflator 32 is disposed at the position of thelower frame 15, it is possible to reduce the weight of the upper portionof the seat back frame 10. Accordingly, it is possible to prevent thedeformation of the seat back frame 10 in the event of collision of thevehicle.

Further, since the inflator 32 is disposed between the front wallportion 15A and the back wall portion 15B of the lower frame 15, it ispossible to protect the inflator 32 from an external shock.

<<2>>

Next, the retainer 34 will be described in detail.

As illustrated in FIGS. 11, 7, and 12, the retainer 34 includes a firstextension portion 134A which protrudes from the casing 33 and extendstoward the seat inner side and a second extension portion 134B whichfaces the outer surface 12A of the plate frame 12.

As illustrated in FIGS. 12 and 9, the stud bolt 36A and the stud bolt36B which are provided in the inflator 32, passing through a firstthrough-hole 134G and a second through-hole 134H formed in the secondextension portion 134B of the retainer 34, protrude toward the seatinner side. Each of the stud bolt 36A and the stud bolt 36B passesthrough the through-hole formed in the plate frame 12.

Then, the inflator 32, the retainer 34, and the plate frame 12 are fixedby fastening a nut to the stud bolt 36A from the seat inner side of theplate frame 12.

Meanwhile, the inflator 32 and the retainer 34 are fixed by fasteningthe nut 37 to the stud bolt 36B. Additionally, the through-hole of theplate frame 12 through which the stud bolt 36B passes has a diameterlarger than that of the nut 37 and the retainer 34 and the plate frame12 are not fixed at this portion.

Further, the webbing clip 60 for fixing a webbing is attached to theplate frame 12 at a position interposing the stud bolt 36A and the studbolt 36B in the vertical direction. Here, the webbing is a member thatguides the deploying direction of the airbag 31 by covering the sideportion of the airbag module 30.

As illustrated in FIG. 11, the outer extension portion 22B of thebracket 20 is attached to the first extension portion 134A of theretainer 34.

Specifically, as illustrated in FIGS. 11 and 12, the first extensionportion 134A is provided with a notch portion 134C which is notched froman end opening portion 134D of the end portion on the seat inner side toa center opening portion 134E at the center portion.

Here, a bead portion 134F which protrudes toward the seat back side isformed in the periphery of the notch portion 134C in the first extensionportion 134A. In this way, since the first extension portion 134A isprovided with the bead portion 134F, the strength of the first extensionportion 134A is improved.

Then, the bolt 24 passes through the through-hole formed in the outerextension portion 22B of the bracket 20 and the notch portion 134C, andthe cap nut 25 is fitted to the end portion 24A of the bolt 24 to befastened thereto. Accordingly, the bracket 20 and the retainer 34 arefixed.

Additionally, according to the above-described configuration, the endportion 24A of the bolt 24 faces the seat back side and the cap nut 25can be fitted thereto from the seat back side. Further, since the endportion 24A of the bolt 24 is covered by the cap nut 25, it is possibleto prevent the inside of the seat back S1 from being damaged by the endportion 24A of the bolt 24.

According to the above-described vehicle seat S, since the bracket 20for attaching the airbag module 30 is attached to the inner surface ofthe side frame 13, it is possible to obtain a compact width of theattachment portion of the airbag module 30 in the right and leftdirection. Further, since the airbag module 30 is attached to the seatback side in relation to the attachment portion between the bracket 20and the side frame 13, it is possible to improve workability whenassembling the airbag module 30 to the bracket 20 from the seat backside.

Further, it is possible to prevent the separation of the retainer 34 andthe side frame 13 which are fixed to each other even when a force isapplied to the retainer 34 in the inner direction of the seat and the upto down direction of the seat.

Further, in the vehicle seat S, the retainer 34 is fixed to the bracket20 attached to the side frame 13 by using the bolt 24 and the cap nut25. In this way, it is possible to easily perform an operation ofattaching the retainer 34 to the side frame 13.

Further, according to the vehicle seat S, it is possible to attach theairbag module 30 to both of the bracket 20 and the outer surface 12A ofthe plate frame 12. Accordingly, it is possible to improve attachmentrigidity as compared with a case in which the airbag module 30 isattached to any one of the bracket 20 and the plate frame 12.

Further, according to the vehicle seat S, since the opening width of theend opening portion 134D of the notch portion 134C is narrower than theopening width of the center opening portion 134E through which the bolt24 is inserted, it is possible to prevent the bolt 24 from beingseparated from the notch portion 134C of the retainer 34 even when aforce is applied to the retainer 34 in the outer direction of the seatafter the retainer 34 is attached to the side frame 13. Accordingly, itis possible to prevent the separation of the retainer 34 and the sideframe 13 which are fixed to each other.

Further, according to the vehicle seat S, since the bead portion 134F isformed in the periphery of the notch portion 134C in the first extensionportion 134A, it is possible to improve rigidity in the periphery of theattachment portion with the side frame 13 in the retainer 34.

Further, according to the vehicle seat S, since the retainer 34 isexposed from a gap between the upper end and the lower end of the casing33 of the airbag module 30, it is possible to obtain the airbag module30 in a compact size.

The vehicle seat according to the present invention includes a sideframe which constitutes a side portion of a seat back frame and anairbag module which is attached to the side frame, in which the airbagmodule includes a retainer which is attached to the side frame, theretainer includes a first extension portion provided behind the sideframe and extending to a seat inner side, the first extension portion isprovided with a notch portion formed from an end portion on the seatinner side toward a seat outer side, and the retainer is fixed to theside frame by using an attachment member inserted through the notchportion.

According to the above-described vehicle seat, it is possible toassemble the airbag module to the side frame of the seat back from theseat back side. Accordingly, it is possible to improve workability whenattaching the airbag module disposed at the side portion of the vehicleseat from the seat back side.

Further, it is possible to prevent the separation of the retainer andthe side frame which are fixed to each other even when a force isapplied to the retainer in the inner direction of the seat and the up todown direction of the seat.

In the above-described vehicle seat, the retainer includes a secondextension portion which is connected to the first extension portion andextends to the seat front side and the second extension portion isattached to the side frame.

In this way, it is possible to attach the retainer to the side frame attwo surfaces. For this reason, it is possible to improve attachmentrigidity of the retainer and the side frame.

In the above-described vehicle seat, the notch portion is fixed to thebracket attached to the side frame and extending toward the seat backside.

In this way, since the bracket attached to the side frame and extendingtoward the seat back side and the retainer are attached, it is possibleto simply fix the retainer and the side frame.

In the above-described vehicle seat, the bracket is fixed to theretainer by a bolt inserted through the notch portion and a nut threadedto the bolt.

In this way, the retainer is fixed to the bracket attached to the sideframe by using the bolt and the nut. Accordingly, it is possible toeasily perform an operation of attaching the retainer to the side frame.

In the above-described vehicle seat, the nut is a cap nut which coversan end portion of the bolt.

In this way, since the end portion of the bolt is covered by the capnut, it is possible to prevent the seat inner portion from being damagedby the end portion of the bolt.

In the above-described vehicle seat, the opening width of the endportion on the seat inner side of the notch portion is narrower than theopening width of the portion through which the bolt is inserted.

In this way, it is possible to prevent the bolt from being separatedfrom the notch portion of the retainer even when a force is applied tothe retainer in the outer direction of the seat after the retainer isattached to the side frame. Accordingly, it is difficult to separate theretainer and the side frame which are fixed to each other.

In the above-described vehicle seat, a bead is formed in the peripheryof the notch portion in the first extension portion.

In this way, it is possible to improve the rigidity in the periphery ofthe attachment portion with the side frame in the retainer.

In the above-described vehicle seat, the airbag module includes theretainer, the airbag, the inflator supplying a gas to the airbag, andthe casing covering the retainer, the airbag, and the inflator and theretainer is exposed from a gap between the upper end and the lower endof the casing.

In this way, it is possible to obtain the airbag module in a compactsize.

The above-described vehicle seat includes a seat back pad which isplaced on the seat back frame and the seat back pad includes a storageportion which is opened in the side portion toward the seat outer sideand stores the airbag module.

In this way, it is possible to attach the airbag module by disposing theairbag module in the storage portion of the seat back pad after the seatback pad is attached to the seat back frame.

<<3>>

Next, another example of an attachment structure of the bracket 20 and aretainer 234 will be described.

The retainer 234 is a plate member for attaching the airbag module 30 tothe seat back frame 10.

As illustrated in FIGS. 13, 14, 16, and 17, the retainer 234 includes aninner extension portion 234A which protrudes from the casing 33 andextends toward the seat inner side and a front extension portion 234Bwhich faces the outer surface 12A of the plate frame 12.

Here, a through-hole is formed at the center portion of the innerextension portion 234A and the bolt 24 (an example of the attachmentportion) inserted through the through-hole is attached so that the endportion of the bolt faces the seat back side (that is, the opposite sideof the extension direction of the front extension portion 234B). Forexample, when the inner extension portion 234A is formed of metal, thebolt 24 may be attached to the inner extension portion 234A by welding.

As illustrated in FIGS. 17 and 9, the stud bolt 36A and the stud bolt36B provided in the inflator 32 protrude toward the seat inner sidethrough the first through-hole 234C and the second through-hole 234Dformed in the front extension portion 234B of the retainer 234. Each ofthe stud bolt 36A and the stud bolt 36B passes through the through-holeformed in the plate frame 12.

Then, a nut is fastened to the stud bolt 36A from the seat inner side ofthe plate frame 12 so that the inflator 32, the retainer 234, and theplate frame 12 are fixed.

Meanwhile, the nut 37 is fastened to the stud bolt 36B so that theinflator 32 and the retainer 234 are fixed. Additionally, thethrough-hole of the plate frame 12 through which the stud bolt 36Bpasses has a diameter larger than that of the nut 37 and the retainer234 and the plate frame 12 are not fixed at this portion.

Further, the webbing clip 60 for fixing a webbing is attached to theplate frame 12 at a position interposing the stud bolt 36A and the studbolt 36B in the vertical direction. Here, the webbing is a member thatguides the deploying direction of the airbag 31 by covering the sideportion of the airbag module 30.

As illustrated in FIGS. 14 and 15, a side surface of the side portion11A of the right pipe frame 11 on the seat inner side is provided withthe through-hole 11B and the through-hole 11C which are formed at theupper and lower sides.

Here, the bracket 20 includes the attachment portion 21 which isattached to the through-hole 11C of the pipe frame 11 and the backprotrusion portion 22 which protrudes from the attachment portion 21backward. Additionally, the back protrusion portion 22 includes the backextension portion 22A which extends from the attachment portion 21toward the seat back side and the outer extension portion 22B whichextends from the back extension portion 22A toward the seat outer side.

As illustrated in FIG. 14, a screw 23 is fastened to the through-holeformed in the attachment portion 21 of the bracket 20 and thethrough-hole 11C formed in the bracket 20 so that the bracket 20 isfixed to the pipe frame 11.

As illustrated in FIG. 14, a bead portion which is recessed toward theseat outer side is formed at the center portion of the back extensionportion 22A. Accordingly, it is possible to improve the strength of theback extension portion 22A.

As illustrated in FIG. 14, the inner extension portion 234A of theretainer 234 is attached to the outer extension portion 22B.

Specifically, as illustrated in FIGS. 14 and 17, the outer extensionportion 22B is provided with a notch portion 22C which is notched froman end opening portion 22D of the end portion on the seat outer side toa center opening portion 22E of the center portion.

Here, a bead portion 22F which protrudes toward the seat back side isformed in the periphery of the notch portion 22C in the outer extensionportion 22B. In this way, since the outer extension portion 22B isprovided with the bead portion 22F, the strength of the outer extensionportion 22B is improved.

Then, the bolt 24 fixed to the retainer 234 passes through the notchportion 22C formed in the outer extension portion 22B of the bracket 20from the end opening portion 22D toward the center opening portion 22E.Then, the cap nut 25 is fitted and fastened to the end portion 24A ofthe bolt 24. Accordingly, the bracket 20 and the retainer 234 are fixed.

Additionally, according to the above-described configuration, the endportion 24A of the bolt 24 faces the seat back side and the cap nut 25can be fitted thereto from the seat back side. Further, since the endportion 24A of the bolt 24 is covered by the cap nut 25, it is possibleto prevent the inside of the seat back S1 from being damaged by the endportion 24A of the bolt 24.

According to the above-described vehicle seat S, since the bracket 20for attaching the airbag module 30 is attached to the inner surface ofthe side frame 13, it is possible to obtain a compact width of theattachment portion of the airbag module 30 in the right and leftdirection. Further, since the airbag module 30 is attached to the seatback side in relation to the attachment portion of the bracket 20 andthe side frame 13, it is possible to improve workability when assemblingthe airbag module 30 to the bracket 20 from the seat back side.

Further, it is possible to prevent the separation of the retainer 234and the side frame 13 which are fixed to each other even when a force isapplied to the retainer 234 in the inner direction of the seat and theup to down direction of the seat.

Further, in the vehicle seat S, the retainer 234 is fixed to the bracket20 attached to the side frame 13 by using the bolt 24 and the cap nut25. In this way, it is possible to easily perform an operation ofattaching the retainer 234 to the side frame 13.

Further, according to the vehicle seat S, it is possible to attach theairbag module 30 to both of the bracket 20 and the outer surface 12A ofthe plate frame 12. Accordingly, it is possible to improve attachmentrigidity as compared with a case in which the airbag module 30 isattached to any one of the bracket 20 and the plate frame 12.

Further, according to the vehicle seat S, since the opening width of theend opening portion 22D in the notch portion 22C of the bracket 20 isnarrower than the opening width of the center opening portion 22Ethrough which the bolt 24 is inserted, it is possible to prevent thebolt 24 from being separated from the notch portion 22C of the bracket20 even when a force is applied to the retainer 234 in the outerdirection of the seat after the retainer 234 is attached to the sideframe 13. Accordingly, it is possible to prevent the separation of theretainer 234 and the side frame 13 which are fixed to each other.

Further, according to the vehicle seat S, since the bead portion 22F isformed in the periphery of the notch portion 22C in the outer extensionportion 22B, it is possible to improve the rigidity in the periphery ofthe attachment portion with the retainer 234 in the bracket 20.

Further, according to the vehicle seat S, the retainer 234 is exposedfrom a gap between the upper end and the lower end of the casing 33 ofthe airbag module 30, it is possible to obtain the airbag module 30 in acompact size.

Further, according to the vehicle seat S, it is possible to fit the bolt24 attached to the retainer 234 from the outside of the notch portion22C of the bracket 20. Accordingly, it is possible to improve theattachment workability of the airbag module 30.

Next, the vehicle seat S according to a modified example of the presentinvention will be described with reference to FIG. 18. In the modifiedexample illustrated in FIG. 18, a bracket 120 has a shape different fromthat of the bracket 20.

That is, as illustrated in FIG. 18, the bracket 120 is different fromthe bracket 20 in that the outer extension portion 22B of the bracket120 is provided with not the notch portion 22C but a through-hole 22G.Additionally, since the vehicle seat S according to the modified examplehas a common point with the above-described embodiment in other points,a description of the common points is omitted.

Here, an operation of attaching the bracket 120 and the retainer 234 ofthe vehicle seat S according to the modified example will be described.

First, the bolt 24 fixed to the retainer 234 is inserted to thethrough-hole 22G formed in the outer extension portion 22B of thebracket 120 toward the seat back side. Then, the cap nut 25 is fittedand fastened to the end portion 24A of the bolt 24. Accordingly, thebracket 120 and the retainer 234 are fixed.

Also in the vehicle seat S according to the modified example, since theretainer 234 of the airbag module 30 can be assembled to the side frame13 from the seat back side, workability can be improved.

Further, in the above-described embodiment, the bracket 20 is attachedto the pipe frame 11 by the screw 23, but the bracket 20 may be attachedto the pipe frame 11 by welding. Additionally, various welding methodssuch as arc welding and laser welding may be used for welding.

Further, a method of fixing the bracket 20 and the retainer 234 is notlimited to the above-described embodiment.

For example, the bracket 20 and the retainer 234 may be fixed by weldingthe back protrusion portion 22 of the bracket 20 and the bolt 24integrated with the retainer 234.

Further, for example, the retainer 234 and the bracket 20 may be fixed,by fitting a push nut to the rod, in a state where the retainer 234 isprovided with a rod which protrudes from the inner extension portion234A backward and the rod is inserted through the notch portion 22C ofthe back protrusion portion 22.

The vehicle seat according to the present invention is a vehicle seatincluding a side frame which constitutes a side portion of a seat backframe, an airbag module which includes a retainer attached to the sideframe, and a bracket which connects the side frame and the airbagmodule, the bracket includes an outer extension portion which isprovided behind the side frame and extends toward a seat outer side, theouter extension portion is provided with a notch portion which is formedfrom an end portion on the seat outer side toward a seat inner side, theretainer includes an inner extension portion which extends toward theseat inner side, and the inner extension portion and the outer extensionportion are fixed by using an attachment portion inserted through thenotch portion.

According to the above-described vehicle seat, it is possible toassemble the airbag module from the seat back side. Further, it ispossible to simply attach the airbag module to the side frame in theinner direction of the seat. Further, it is possible to prevent theairbag module from being separated from the side frame even when a shockis applied in the inner direction of the seat and the up to downdirection of the seat after the airbag module is attached to the sideframe.

Further, in the above-described vehicle seat, the inner extensionportion is disposed behind the outer extension portion.

In this way, it is possible to perform an operation of fixing thebracket and the retainer from the back side of the bracket.

Further, in the above-described vehicle seat, the retainer includes afront extension portion which is connected to the inner extensionportion and extends toward the seat front side and the front extensionportion is attached to the side frame.

In this way, it is possible to attach the retainer to the side frame attwo surfaces. For this reason, it is possible to improve the attachmentrigidity of the retainer and the side frame.

Further, in the above-described vehicle seat, the bracket is attached toa side surface of the side frame on the seat inner side.

In this way, it is possible to obtain a compact width of the attachmentportion of the airbag module in the right and left direction.

Further, in the above-described vehicle seat, the retainer includes theattachment portion and the attachment portion includes a portion whichprotrudes from the inner extension portion backward.

In this way, it is possible to easily perform an operation of fixing thebracket and the retainer to each other.

Further, in the above-described vehicle seat, the bracket is fixed tothe retainer by a bolt inserted through the notch portion and a nutthreaded to the bolt.

In this way, the retainer is fixed to the bracket attached to the sideframe by using the bolt and the nut. Accordingly, it is possible toeasily perform an operation of attaching the retainer to the side frame.

In the above-described vehicle seat, the nut is a cap nut which coversan end portion of the bolt.

In this way, since the end portion of the bolt is covered by the capnut, it is possible to prevent the seat inner portion from being damagedby the end portion of the bolt.

Further, in the above-described vehicle seat, the outer extensionportion is provided with a bead formed in the periphery of the notchportion.

In this way, it is possible to prevent the bolt from being separatedfrom the notch portion of the retainer even when a force is applied tothe retainer in the outer direction of the seat after the retainer isattached to the side frame. Accordingly, it is difficult to separate theretainer and the side frame which are fixed to each other.

Further, in the above-described vehicle seat, the airbag module includesthe retainer, the airbag, the inflator supplying a gas to the airbag,and the casing covering the retainer, the airbag, and the inflator andthe retainer is exposed from a gap between the upper end and the lowerend of the casing.

In this way, it is possible to improve the rigidity in the periphery ofthe attachment portion with the side frame in the retainer.

Further, it is preferred that the above-described vehicle seat includesthe seat back pad which is placed on the seat back frame and the seatback pad includes the storage portion which is opened in the sideportion toward the seat outer side and stores the airbag module.

In this way, it is possible to obtain the airbag module in a compactsize.

Further, it is preferred that, in the above-described vehicle seat, theside frame includes a cylindrical pipe frame and a plate-shaped plateframe attached to a lower portion of the pipe frame, and the airbagmodule is attached to a side surface of the plate frame on a seat outerside.

In this way, it is possible to attach the airbag module to both of thebracket and the side surface of the plate frame on the seat outer side.Accordingly, it is possible to strongly attach the airbag module to theseat cushion frame as compared with a case in which the airbag module isattached to any one of the bracket and the plate frame.

REFERENCE SIGNS LIST

-   S: VEHICLE SEAT    -   S1: SEAT BACK    -   S2: SEAT CUSHION    -   S3: HEADREST-   1: SEAT BACK PAD    -   1A: STORAGE PORTION-   2: SKIN-   10: SEAT BACK FRAME-   11: PIPE FRAME    -   11A: SIDE PORTION    -   11B: THROUGH-HOLE    -   11C: THROUGH-HOLE    -   12: PLATE FRAME    -   12A: OUTER SURFACE-   13: SIDE FRAME-   14: CROSS MEMBER-   15: LOWER FRAME    -   15A: FRONT WALL PORTION    -   15B: BACK WALL PORTION-   20: BRACKET-   21: ATTACHMENT PORTION-   22: BACK PROTRUSION PORTION    -   22A: BACK EXTENSION PORTION    -   22B: OUTER EXTENSION PORTION    -   22C: NOTCH PORTION    -   22D: END OPENING PORTION    -   22E: CENTER OPENING PORTION    -   22F: BEAD PORTION    -   22G: THROUGH-HOLE-   23: SCREW-   24: BOLT    -   24A: END PORTION-   25: CAP NUT-   30: AIRBAG MODULE-   31: AIRBAG-   32: INFLATOR-   33: CASING-   34: RETAINER    -   34A: PROTRUSION PORTION    -   34B: INNER EXTENSION PORTION    -   34C: OPENING PORTION    -   34D: FLAT PLATE PORTION-   35: HARNESS    -   36A: STUD BOLT    -   36B: STUD BOLT-   37: NUT-   38: PIPE-   40: AIRBAG MODULE-   41: SIDE PLATE-   42: SCREW    -   50A: WELDED PORTION    -   50B: WELDED PORTION-   60: WEBBING CLIP-   120: BRACKET    -   134A: FIRST EXTENSION PORTION    -   134B: SECOND EXTENSION PORTION    -   134C: NOTCH PORTION    -   134D: END OPENING PORTION    -   134E: CENTER OPENING PORTION    -   134F: BEAD PORTION    -   134G: FIRST THROUGH-HOLE    -   134H: SECOND THROUGH-HOLE-   234: RETAINER    -   234A: INNER EXTENSION PORTION    -   234B: FRONT EXTENSION PORTION    -   234C: FIRST THROUGH-HOLE    -   234D: SECOND THROUGH-HOLE

The invention claimed is:
 1. A vehicle seat comprising: a side framewhich constitutes a side portion of a seat back frame; a bracket whichincludes an attachment portion attached to a side surface of the sideframe on a seat inner side and a back protrusion portion protrudingbackward from the attachment portion; and an airbag module which isfixed to the back protrusion portion, wherein the back protrusionportion includes a back extension portion which extends backward fromthe attachment portion and an outer extension portion which extends froma back end of the back extension portion toward a seat outer side, andwherein the airbag module is attached to a back surface of the outerextension portion that faces backward.
 2. The vehicle seat according toclaim 1, wherein the side frame includes a cylindrical pipe frame and aplate-shaped plate frame attached to a lower portion of the pipe frame,and wherein the airbag module is attached to a side surface of the plateframe on a seat outer side.
 3. The vehicle seat according to claim 2,wherein the bracket is attached to a lower portion in relation to ajoint portion between the pipe frame and the plate frame in the pipeframe.
 4. The vehicle seat according to claim 1, wherein the airbagmodule includes an airbag, an inflator which supplies a gas to theairbag, a casing which covers the inflator and the airbag, and aretainer including a protrusion portion which protrudes from the casing,and wherein the outer extension portion of the bracket and theprotrusion portion of the retainer are fixed.
 5. The vehicle seataccording to claim 4, wherein the outer extension portion of the bracketand the protrusion portion of the retainer are fixed by fastening a nutto a bolt penetrating both portions, and wherein the protrusion portionof the retainer is provided with an opening portion through which thebolt is inserted.
 6. The vehicle seat according to claim 5, wherein theprotrusion portion of the retainer includes an inner extension portionwhich is provided on a back side of the side frame to extend toward theinner side of the seat, and wherein the inner extension portion and theouter extension portion are fixed.
 7. The vehicle seat according toclaim 6, wherein an end portion of the bolt faces backward, and whereinthe nut is a cap nut which covers the end portion of the bolt.
 8. Thevehicle seat according to claim 6, wherein the opening portion of theretainer is provided across an end portion on the inner side of theseat.
 9. The vehicle seat according to claim 1, further comprising: aseat back pad which covers the seat back frame, wherein the seat backpad includes a storage portion which is opened in the side portiontoward a seat outer side and stores the airbag module.